1. Field of the Invention
The present invention relates to an optical module utilized in an optical transceiver and the like for linking and unlinking.
2. Related Background Art
In high-speed LANs (Local Area Networks), optical transceivers have widely been in use as a module for converting digital electric signals and optical signals to each other. In order to attain a higher density in ports of hub apparatus and the like using such optical transceivers, SFF (Small Form Factor) has been known as a unified standard enabling a smaller size. While such SFF optical transceivers are characterized by their small size and low power consumption, SFP (Small Form Factor Pluggable) optical transceivers making electric connectors attachable thereto and detachable therefrom without stopping devices have further been developed.
As LANs attain a higher speed, digital signals transmitted by such an SFF or SFP optical transceiver have been shifting to a gigabit band. It is necessary for SFP optical transceivers to restrain performances from deteriorating upon attaching/detaching, since they are assumed to be subjected to a number of attaching/detaching operations. In an SFP optical transceiver, a circuit board, a light-emitting device unit, and a light-receiving device unit are arranged like a single line, whereas the attaching/detaching direction of optical and electric connectors aligns with this line, whereby stresses applied to the connecting parts between the circuit board and the light-emitting/receiving device unit may vary upon attaching/detaching, thus yielding fear of breakage and deterioration.
Therefore, it is an object of the present invention to provide an optical module used in an optical transceiver and the like, which can restrain its characteristics from deteriorating even when attaching/detaching operations are repeated.
For achieving the above-mentioned object, the present invention provides an optical module comprising, within a housing, a substrate having an electronic circuit, and light-emitting and light-receiving device units each having an optical output or input end connected to the electronic circuit; wherein the light-emitting device unit and the light-receiving device unit have respective cylindrical leading end parts accommodated in substantially cylindrical holes within the housing and respective flange parts having diameters greater than those of the leading end parts, the housing having an inclined wall behind the substantially cylindrical holes; and wherein the optical module further comprises a pressing member having a protrusion for pressing the flange parts of the light-emitting device unit and light-receiving device unit against the housing so as to secure said units, the pressing member engaging the housing while being slid along the inclined wall of the housing by a slanted wall provided so as to correspond to the inclined wall.
As a consequence of such a configuration, the light-emitting device unit and the light-receiving device unit are pressed and secured within the housing by the pressing member. Therefore, the force received by the light-emitting/receiving device unit upon attaching/detaching optical connection is absorbed by the pressing member, and thus is not transmitted to the connecting part with respect to the electronic circuit, where by breakage and the deterioration of connecting parts can be prevented from occurring. Hence, performances can be restrained from deteriorating upon attaching/detaching.
Preferably, the pressing member engages a cutout of the housing by way of an elastic protrusion having a claw at a leading end thereof. This enables reliable engagement.
Preferably, the tilted wall has a wall face forming an angle of 40xc2x0 to 80xc2x0 with respect to a horizontal plane of the substrate. As a consequence, the light-emitting device unit and the light-receiving device unit can reliably be pressed when attaching the pressing member.
The present invention will become more fully understood from the detailed description given hereinbelow and the accompanying drawings which are given by way of illustration only, and thus are not to be considered as limiting the present invention.
Further scope of applicability of the present invention will become apparent from the detailed description given hereinafter. However, it should be understood that the detailed description and specific examples, while indicating preferred embodiments of the invention, are given by way of illustration only, since various changes and modifications within the spirit and scope of the invention will become apparent to those skilled in the art from this detailed description.